High-speed printer

ABSTRACT

A high-speed printer is operative for printing alphanumerical characters by selecting dots of a matrix composed of dots arranged in identical parallel columns which are spaced from each other in the direction of a line of alphanumerical characters to be printed. The printer includes a printing head including printing elements arranged in form of a single one of the mentioned columns. A drive motor moves the printing head along a predetermined path extending in the direction of the line of characters to be printed. A detector arrangement detects the arrival of the printing head at successive predetermined locations along the path of movement of the latter. A synchronizing arrangement generates successive synchronizing signals in response to detection by the detector arrangement of the arrival of the printing head at successive ones of said predetermined locations. A character-generating unit connected to the synchronizing arrangement receives successive synchronizing signals and furnishes to the printing elements successive groups of signals, each group signifying which dots of the column are to be printed, and each group being furnished to the printing elements in synchronism with the receipt by the charactergenerating unit of one of said synchronizing signals.

United States Patent 1 Sauerbrunn 1 HIGH-SPEED PRINTER [75] Inventor:Wolfgang Sauerbrunn,Gerlingen,

Germany [22] Filed: Oct. 24, 1973 [21] App]. No.: 409,336

[30] Foreign Application Priority Data Oct. 27, 1972 Germany 2252767[52] US. Cl. 197/1 R; l01/93.l5 [51] Int. Cl B41j 3/05 [58] Field ofSearch 197/1 R, 49, 48; 101/93 C [56] References Cited UNITED STATESPATENTS 3,459,287 8/1969 Avins et a1. 197/1 R 3,690,431 9/1972 Howard197/1 R 3,703,949 11/1972 Howard et a1. 197/1 R 3,752,288 8/1973 Detiget al. 197/1 R 3,757,346 9/1973 Holland 197/1 R 3,802,544 4/1974 Howardct al. 197/1 R Primary Examiner-Edgar S. Burr Assistant ExaminerR. T.Rader Attorney, Agent, or FirmMichael S. Striker 57 ABSTRACT Ahigh-speed printer is operative for printing alphanumerical charactersby selecting dots of a matrix composed of dots arranged in identicalparallel columns which are spaced from each other in the direction of aline of alphanumerical characters to be printed. The printer includes aprinting head including printing elements arranged in form of a singleone of the mentioned columns. A drive motor moves the printing headalong a predetermined path extending in the direction of the line ofcharacters to be printed. A detector arrangement detects the arrival ofthe printing head at successive predetermined locations along the pathof movement of the latter. A synchronizing arrangement generatessuccessive synchronizing signals in response to detection by thedetector arrangement of the arrival of the printing head at successiveones of said predetermined locations. A character-generating unitconnected to the synchronizing arrangement receives successivesynchronizing signals and furnishes to the printing elements successivegroups of signals, each group signifying which dots of the column are tobe printed, and each group being 'fumished to the printing elements insynchronism with the receipt by the character-generating unit of one ofsaid synchronizing signals.

20 Claims, 1 Drawing Figure HIGH-SPEED PRINTER I BACKGROUND or THEINVENTION ical characters are registered in dotor point-matrix speeds.The synchronization between the column-bycolumn read out of thecharacter generator is more assumed than actual, and the advancement ofthe printing electrodes, under the control of the stepper motor,

can easily fall out of phase with the column-by-column read-out of thecharacter generator. Evidently, the distance actually advanced by theset of printing electrodes, in response to the receipt by the drivingstepper motor of a triggering pulse'to cause the advancement of themotor output shaft by one step, will depend upon the instantaneous speedof the motor at the time that the triggering pulse is received, theinertia of the rotating parts of the motor being a significant factorwhen form, the points of the matrix being arrangedv in horizontal rowsand vertical columns. The character generator has one output for eachhorizontal row of the point matrix, and the character generator is readout in such a manner that the signals corresponding to the informationunits associated with each successive vertical column of the pointmatrix appear simultaneously at the plurality of outputs of thecharacter generator. Thus, the successive vertical columns of the pointmatrix encoding of the alphanumerical character are read out, column bycolumn. The character generator has a plurality of column-selectioninputs, one for each vertical column of the point-matrix. When aselection signal is applied to one of these column-selection inputs,there appear at the plurality of outputs of the character generator thesignals associated with the constituent points of the respective columnof the point-matrix. Columnselection signals are applied to thecolumn-selection inputs in succession, so as to effect thecolumn-bycolumn read-out of the point-matrix arrangement of informationstored in the character generator. The character generator cooperateswith a set of printing electrodes, equal in number to the outputs of thecharacter generator and accordingly equal in number to the horizontalrows of the point-matrix. The set of printing electrodes prints onto aroll of paper or the like successive groups of points, in accordancewith the particular combination of output signals appearing at theoutputs of the signal generator at any one time.

High-speed printers of this type are already known. In the knownconstructions, the set of printing electrodes is moved back and forthalong the line to be printed, which may for example extend in directiontransversely to the elongation of the elongated and rolled-up paper uponwhich the printing is performed. The drive motor for the advancement ofthe set of printing electrodes along the line to be printed is a stepper motor. With that particular type of high-speed printer, triggeringpulses for the stepper motor are generated simultaneously with thegeneration of columnselection pulses for the column-by-column read outof the character generator. in establishing such an expedient, theassumption is that the stepper motor will be turned in preciselycontrolled manner as triggered by the triggering pulses and that thecolumn-by-column read-out of the character generator will occur in exactsynchronism therewith, so that after a particular column of thepoint-matrix stored in the character generator is readout, the next suchcolumn will be read-out exactly at the time that the moving set ofprinting electrodes reaches the position on the line to be printed atwhich the points corresponding to such column are to be located.Unfortunately such exact synchronization cannot be realized, except atrelatively low printing very high speeds of operation are involved.Moreover, his not possible to maintain the speed of the stepper motorexactly constant, and the tendency of the motor to exhibit periodicspeed variations will increase with increasing motor speed. As a resultof these factors, the printing speed of the known printer is limited toabout characters per second, with the printing proceeding with goodprinting quality at a printing speed of about 30 characters per second,but being only just acceptable when the printing speed is at about 100characters per second.

SUMMARY OF THE INVENTION It is the general object of the invention toprovide a high-speed printing arrangement, particularly such as would beused for print-out purposes in a digital computer, which can printeffectively and reliably at printing speeds substantially higher thanwas possible with prior-art printing arrangements of the general type inquestion.

This object, and others which will become more understandable from thefollowing description, can be met according to one advantageous conceptof the invention, by providing, in a high-speed printer of the typeoperative for printing alphanumerical characters by selecting dots of amatrix composed of dots arranged in identical parallel columns which arespaced from each other in the direction of a line of alphanumericalcharacters to be printed, in combination, a printing head includingprinting elements arranged in form of a single one of said columns.Drive means moves the printing head along a predetermined path extendingalong said direction. Detecting means detects the arrival of theprinting head at successive predetermined locations along the path oftravel thereof. Synchronizing means generates successive synchronizingsignals when said detecting means detects the arrival of the printinghead at successive ones of said predetermined locations.Character-generating means connected to said synchronizing meansreceives said successive synchronizing signals and furnishes to theprinting elements successive groups of signals, each group signifyingwhich dots of the column are to be printed, and the character-generatingmeans furnishing each successive group of signals to the printingelements upon receipt of one of said synchronizing signals.

As a result, it is possible to achieve a distortionless print out atvery high printing speeds, in virtually complete independence from theactual speed of the drive motor, inasmuch as according to the concept ofthe present invention the column-by-column read-out of the point-matrixcharacter generator is more directly synchronized with the distancetravelled by the moving printing head than was the case with theprior-art approach. Even very sizable variations in motor speed will notresult in a loss of synchronism, inasmuch as any such motor speedvariations will to a very considerable extent be automaticallycompensated for by corresponding changes in the speed of thecolumn-bycolumn read-out of the point-matrix character generator. As aresult, the drive motor can be of almost any convenient type, forexample a stepper motor or a DC. motor or a polyphase AC. motor. It isonly necessary that the driving motor, or the means which converts therotational motion of the motor into translational movement of theprinting head, be reversible, so that the printing head can at the endofa line be returned to the beginning of the next line to be printed.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING The single FIGURE depicts in schematicmanner one exemplary embodiment of the inventive concept.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the FIGURE, referencenumeral designates a source of information signals. The informationsource 10 can be in the form of a magnetic tape storage or a perforatedtape storage, or can be the output of a computer. The information source10 has six outputs each of which is either energized or leftunenergized. With six such outputs, there are evidently 2 64 differentpossible combinations of energized and unenergized outputs, andaccordingly the information source 10 is capable of generating 64different output signals.

The information source 10 has an input for the receipt of an advancementpulse which causes the information source 10 to present at the sixoutputs thereof a signal corresponding to the next unit of informationin the succession of units of information stored therein or 'furnishthereby. For example, the information source 10 may be comprised of anelongated perforated tape having six parallel tracks, and a set of sixphotoelectric detector elements arranged transverse to the elongation ofthe tape, with advancing means provided for moving the tape relative tothe photoelectric detectors by a distance corresponding to the minimumdistance been successive perforations of one track, in response to thereceipt by the information source 10, at the illustrative input thereof,of a tape-advancement signal.

The six outputs of the information source 10 are connected to respectiveones of the six inputs of a character generator 11 provided in the formof a readonlymemory (ROM) unit. The character generator 11 is capable ofgenerating 64 different alphanumerical characters, the characteractually generated being determined by which one of the 64 differentpossible combinations of input signals is applied to the six inputsthereof. Each character is stored in the form of 35 separate units ofinformation, in correspondence to the 5 X 7 point-matrix form in whicheach generated character is ultimately to be printed. Specifically. theunits of information stored in the read-only-memory unit 11 are storedin a manner corresponding to five vertical columns and seven horizontalrows of a point-matrix. Each of these thirty-five units of informationmay be a logic 1 signal or a logic 0 signal, in dependence upon thesignals applied to the six inputs of the character generator 1 l.

The character generator 11 has seven outputs designated I, II, III, IV,V, VI and VII, in correspondence to the seven horizontal rows of thepoint-matrix form in which the character represented by the informationstored in generator 11 is ultimately to be printed. It is emphasizedthat the character generator 11 in question is per se a conventionalcomponent.

The character generator 11 is provided with five column-section inputs,designated 1, 2, 3, 4, 5. When a column-selection signal is applied toone of these five inputs 1-5, there appears at the seven outputs I-VIIof the character generator 11 a set of seven signals corresponding tothe seven units of information representative of the constituentelements of the respective vertical column of the point-matrix characterto be printed. Column selection signals are applied to the five inputs1, 2, 3, 4, 5 in succession and cyclically.

The seven outputs I-VIl of the character generator 11 are connected toseven inputs of an amplifier stage 12. The seven outputs of theamplifier stage 12 are connected to a set of seven aligned printingelements, such as printing electrodes. These printing electrodes arecontained within a printing head 13 and are arranged in a verticalcolumn, as considered with respect to the direction in which printedmaterial is read by a human reader.

Reference numeral 14 designates an elongated sheet of paper wound off anon-illustrated paper supply roll. The printing head 13 is mounted formovement (by non-illustrated guide means) in direction transverse to theelongation of the elongated sheet'l4, back and forth in the directionalong which a line of alphanumerical characters is printed.

The drive means for the printing head 13 is comprised of a wire 14'which is taughtly guided around two guide rollers 15 and 16, with thewire l4'being fixedly connected to the printing head 13. Referencenumerals 33 and 34 designate two alphanumerical characters which havebeen printed in point-matrix form on the sheet I4, the charactersillustrated being the capital letters A and E. It will be noted that theprinted characters 33 and 34 are spaced from each other a predetermineddistance corresponding to the normal separation between successivecharacters. The drive wire 14' is driven by a stepper motor 17, throughthe intermediary of the guide and drive roller 16.

Mounted on the motor shaft 18 of the stepper motor 17 is a coded disk19, and coded disk 19 rotating in unison with the motor shaft 18. Thecoded disk 19 is provided with markings so spaced and arranged as toserve for the properly synchronized generation of columnselectionsignals to be applied to the column-selection inputs 1, 2, 3, 4, 5 ofthe character generator 11.

Specifically. the coded disk 19 is marked with a plurality of radiallyextending lines 20, arranged in circumferentially spaced groups of fivelines each. A photoelectric detector unit 21, of conventional nature, isprovided to generate a succession of pulses upon movement thereby of thesuccessive radially extending lines 20. The sequence of pulses generatedby photoelectric detector unit is applied to the input of an amplifier22. The amplified signals appearing at the output of the amplifier 22are thereafter applied to a pulse-shaping stage 23, such as a monostablemultivibrator. The pulse appearing at the output of pulse-shaping stage23 are uniform rectangular pulses. The pulses appearing at the output ofpulse-shaping stage 23 are thereafter applied to the counting input of a4-bit binary counter 24. The binary outputs of the 4-bit binary counter24 are connected to the binary inputs of a binary-to-decimal decoder 25,the decimal outputs of which are connected to the column-selectioninputs 1, 2, 3, 4, 5 of the character generator 11.

The 4-bit binary counter 24 must be reset after the receipt of each setof five successive pulses from the output of pulse shaper 23. To thisend, the binary counter 24 is provided with a reset input connected tothe output of pulse-shaper 29 to receive therefrom a reset pulse. Areset pulse is applied to the reset input of binary counter 24intermediate the application thereto of the successive groups of fivepulses each from the output of pulse shaper 23. To this end, the codeddisk 19 is provided with a plurality of radially extending lines 26located intermediate the successive circumferentially spaced groups offive lines 20, and located nearer to the axis of rotation of the diskthan the lines 20, so as not to be detectable by the photoelectricdetector 21 for the lines 20. A second photoelectric detector 27 isprovided for the detection of the movement past detector 27 of the lines20. The photoelectric detector 27, as well as the photoelectric detector21, can be provided in the form of a light source cooperating with aphototransistor or other lightresponsive semiconductor element orcircuit. The disk 19 can be of transparent or translucent material, andthe lines 20 and 26 can be opaque, or vice versa. Also, the markings onthe disk 19 could be detected by means other than photoelectric means,such as mechanical contact feelers, pneumatic means,magneticfield-responsive means, etc. Furthermore, the disk 19 itselfcould be replaced by a rotating cylinder, with the markings 20 and 26being provided on the circumferential periphery of the cylinder.

In any event, when the photoelectric detector 27 detects a radiallyextending line 26, it applies a pulse to amplifier 28. The amplifierpulse at the output of amplifier 28 is applied to a furtherpulse-shaping stage 29, which may for example be a monostablemultivibrator. The pulse appearing at the output of the pulse-shapingstage 29 constitutes a reset pulse for the binary counter 24 and isapplied to the reset input thereof.

The fifth output of the binary-to-decimal decoder is connected to theadvancement pulse input of the information source 10. Moreover, theinformation source is responsive to the trailing edge of the pulsereceived at such advancement pulse input. For example, the informationsource 10 may be comprised of a differentiator stage having an inputconnected to the fifth decimal output of the decoder 25. Thus, suchdifferentiator would generate a positive-going and a negativegoingvoltage spike in response to the appearance on the fifth output ofdecoder 25 of the leading and trailing edges of the generated pulse,respectively. A halfwave rectifier could be connected to the output ofsuch differentiator stage for the purpose of passing only thenegative-going voltage spike corresponding to the trailing edge of thepulse appearing on the fifth output of the decoder 25, and thisnegative-going voltage spike I can be employed to drive a stepper motorfor effecting advancement of the perforated tape in information source10 by a unit distance, so that the signals at the six outputs of source10 will now correspond to the next character to be printed. Theexpedient of triggering advancement of the perforated tape ininformation source 10 at the moment of the trailing edge of the last ofthe five column selection pulses leads to the advantageous result thatsuch tape advancement will be completed before the time that the nextcolumn-selection pulse, applied to column-selection input 1, isgenerated. It will be understood that the printing head 13, uponcompletion of the printing of the character 33, for example, will move adistance corresponding to the normal separation between characters,before commencing the printing of the character 34. This time intervalwill be sufficient for the advancement of the perforated tapein.information source 10 by a unit distance.

As mentioned before, the printing head 14 is movable along a horizontalline (as viewed in the FIGURE), in both rightwards and leftwardsdirections, due to the provision of suitable mounting means. Themounting means may have the form of a (non-illustrated) guide rail whichis engaged by the printing head 14 and slides therealong. Other mountingexpedients will be evident to those skilled in the art, and do not perse form part of the present invention. As will be evident to thoseskilled in the art, the rightwards movement (as viewed in the FIGURE) ofthe printing head 13 should continue only until the printing head 13reaches the end of a line to be printed, whereafter the printing head 13should travel in leftwards direction back to its starting position;likewise, its leftwards travel should be terminated when it in factreaches its starting position. To this end, the printing head 13 isprovided with a member 30 having a leftwards projecting portion and arightwards projecting portion. When the printing head 13 movesrightwards to such an extent that it reaches the end of the line to beprinted, the right-hand end of the member 30 enters into a photoelectricdetector unit 32 which generates a signal which causes the motor 20 torotate in the reverse direction, to cause the printing head to travel inleftwards direction back towards its starting position. When theprinting head 13 has travelled in leftwards direction to such an extentas to have reached its initialor starting position, the left-hand portion of the member 30 will enter into the photoelectric detector unit 31and generate a signal which causes the motor 22 to again turn in theoriginal direction, causing the printing head 13 to again travel acrossthe sheet 14 in rightwards direction. The signal which is generated byphotoelectricdetector 32 when the printing head 13 reaches anend-of-line position can also be applied to means for rolling up thesheet 14, so that such rolling up can be effected during thereturn-movement of the printing head 13, so that the sheet 14 will be inproper position by the time the printing head 13 returns to its initialor starting position. Furthermore, the signal generated by thephotoelectric detector 32 when the reading head 13 reaches theend-of-line position can furthermore be employed to activate(non-illustrated) electronic switch means to disable the photoelectricdetectors 21 and 27, or alternatively the binary counter 24, during thereturn movement of the printing head, so that no printing of informationwill occur during the return movement of the printing head, despite thefact that the synchronizing lines 20 and 26 are moving past thephotoelectric detectors 21 and 27. i

The means for reversing the direction of rotation of motor 22 inresponse to generation of a signal by unit 32, the means for againreversing the direction of rotation of motor 22 in response togeneration of a signal by unit 31, and the means for disabling thephotoelectric detectors 21 and 27 during the return movement of theprinting head 13, have not been illustrated or described in detail,inasmuch as the circuitry involved is evidently of a routine andconventional nature.

In the illustrated embodiment identical synchronizing markings 20 areprovided on the synchronizing disk 19. The synchronizing pulses derivedtherefrom and appearing at the output of pulse-shaper 23 are applied tothe combination of the binary counter 24 and the decoder 25, whichtogether cooperate to apply columnselection signals to successive onesof the columnselection inputs l of the character generator 11. Afunctionally equivalent but distinct alternative would be to replace thefive identical markings of each group of synchronizing markings withfive distinguishable markings, for example, five markings located atdifferent radial distances from the motor shaft 18. A separatephotoelectric detector could be provided for the detection of each ofthe five distinguishable synchronizing markings, and the output of eachof such five photoelectric detectors could be connected directly to thefive column-selection inputs l-5 of the character generator 11.

An important concept of the invention is the idea of synchronizing thegeneration of the column-selection signals with positive detection ofthe arrival of the moving printing head at predetermined positions alongits path of travel. In the illustrated embodiment, the detection of theposition of the printing head is made some what indirectly, bydetecting, in effect, the position of the motor output shaft whichdrives the printing head. A further but distinct possibility would be todetect the position of the printing head in a still more direct manner,for example by providing successive synchronizing markings right alongthe path of movement of the printing head and providing a photoelectricdetector on the printing head. However, irrespective of whether thelatter alternative is employed, or whether the illustrated approach isemployed, it will be appreciated that the concept according to theinvention is a marked departure from prior-art practice. In the priorart, the triggering pulses for the stepper motor and the columnselectionpulses for the character generator were generated simultaneously, theassumption being that the movement of the printing head would besynchronized with the cyclical energization of the column-selectioninputs. However, as explained earlier, this'synchronization was merelyan assumed synchronization, whereas the synchronization achieved withthe approaches according to the present invention is a much moreeffective synchronization, establishing a more direct relationshipbetween the position of the moving printing head and the generation ofthe successive columnselection signals.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofcircuits and constructions differing from the types described above.

While the invention has been illustrated and described as embodied in ahigh-speed printer, it is not intended to be limited to the detailsshown, since various modifications and structural changes may be madewithout departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended:

l. A high-sped printer for alphanumerical characters,

comprising a printing head driven back and forth along a band-shapedcharacter record by means of a reversible drive motor and comprised of rprinting elements adapted to print as many as r dots in a column; acharacter generator for registering characters in the form of a dotmatrix composed of c columns and r rows and provided with r informationoutputs and 0 columnselection inputs and operative for presenting atsaid r outputs signals representing the dots in the column correspondingto whichever one of saidc inputs has a selecting signal applied thereto,said r outputs being connected to said r printing elements; and readingmeans for reading out said character generator column-bycolumn and forcausing said r printing elements to print the corresponding dot-matrixalphanumerical character column-by-column, by cyclically applyingselecting signals to successive ones of said 6 inputs, said readingmeans comprising a coded disk mounted on and rotating in synchronismwiththe outputshaft of the drive motor and provided with synchronizingmarkings ar-- ranged in first and second concentric tracks, the firsttrack containing at least one group of c equiangularly spaced markingsrespectively corresponding to said 6 column-selection inputs, and thesecond track containing at least one reset marking, first and seconddet'ec tors respectively detecting the markings in the first and secondtracks and generating corresponding first and second synchronizingsignals, a binary counter having a clock input and a reset inputrespectivelyconnected to the outputs of said first and second detectorsfor receipt of said first and second synchronizing signals,respectively, and a binary-to-decimal decoder havings its inputsconnected to the binary counter outputs and having 0 outputsrespectively connected to said c column-selection inputs for applyingselecting signals to the latter, and wherein said reset marking in saidsecond track is 'angularly offset relative to said group of markings insaid first track such that resetting of said binary counter occurssubsequent to the printing by said printing head of a completecharacter.

direction; detecting means operative for detecting the arrival of saidprinting head at successive predetermined locations along said path andoperative for generating successive synchronizing signals in response tothe detection of the arrival of said printing head at successive ones ofsaid predetermined locations, said detecting means comprising aninformation carrier bearing synchronizing markings, reading meanspositioned to read said markings and generate said synchronizingsignals, and means for effecting relative movement between saidinformation carrier and said reading means in direct correlation withthe movement of said printing head along said predetermined path, andwherein said synchronizing markings are arranged in spaced groups, thesynchronizing markings within each group being equidistantly spaced fromeach other by a first distance corresponding to the equal spacingbetween the dotmatrix columns of one dot-matrix alphanumerical characterto be printed, and wherein adjoining ones of said spaced groups arespaced from each other by a different second distance corresponding tothe spacing be tween successive alphanumerical characters to be printed,and wherein the spaces intermediate successive ones of said groups aredevoid of synchronizing markings like the synchronizing markingscontained in said groups; and character-generating means connected tosaid reading means and operative upon receipt of said successivesynchronizing signals for furnishing to said printing elementssuccessive groups of signals, each group signifying which dots of adotmatrix column are to be printed.

3. The printer defined in claim 2, wherein said information carrier isan endless information carrier.

4. The printer defined in claim 3, wherein said information carrier is acircular information carrier.

5. The printer defined in claim 4, wherein said means for effectingrelative movement between said information carrier and said readingmeans comprises means connecting said circular information carrier tosaid drive means torotate said circular information carrier in exactsynchronism .with the operation of said drive means.

6. The printer defined in claim 5, wherein said drive means comprises amotor having a rotatable output shaft and means interconnecting saidrotatable output shaft and said printing head for converting therotational movement of said output shaft into movement of said printinghead along said path, and wherein said circular information carrier ismounted on said rotatable output shaft for rotation therewith.

7. The printer defined in claim 2, wherein said character-generatingmeans comprises input means for receiving a character-indicating signalindicative of which alphanumerical character is to be generated, aplurality of column-selection inputs equal in number to the columns ofthe dot-matrix format in which said alphanumerical characters areprinted, and a plurality of outputs equal in number to the horizontalrows of the dot-matrix format in which said alphanumerical charactersare printed and connected to said printing elements, connecting meansconnected to said detecting means for receipt of said synchronizingsignals and connected to said column-selection inputs and operative forapplying a column-selection signal to successive ones of saidcolumn-selection inputs in synchronism with the receipt of synchronizingsignals from said detecting means, and means operative in response tothe application of a column-selection signal to one of saidcolumn-selection inputs for presenting at said plurality of outputs agroup of signals signifying which dots of the corresponding column areto be printed by said printing elements.

8. The printer defined in claim 7, wherein said detecting means isprovided with a synchronizing signal output and comprises means forgenerating successive groups of identical synchronizing signals at saidsyrichronizing signal output, the successive groups of identicalsynchronizing signals each consisting of a number of signals equal tothe number of columns in said dotmatrix format, and wherein saidconnecting means comprises counter means having an input connected tosaid synchronizing signal output for receiving said successive groups ofidentical synchronizing signals and having a plurality of outputsconnected to different respective ones of said column-selection inputsand operative for applying a column-selection signal to successive onesof said column-selection inputs in synchronism with the receipt by saidcounter means of the constituent signals of each of said groups ofidentical synchronizing signals.

9. The printer defined in claim 7, wherein said detecting meanscomprises signal-generating means for generating successive groups ofdistinguishable synchronizing signals at a plurality of outputs, thesuccessive groups of distinguishable synchronizing signals eachconsisting of a number of signals equal to the number of columns in saiddot-matrix format, and wherein said connecting means comprises meansconnecting said plurality of outputs of said signalgenerating means tosaid column-selection inputs and operative for applying acolumn-selection signal to different ones of said column-selectioninputs in dependence upon which one of said distinguishablesynchronizing signals is received by said connecting means.

10. The printer defined in claim 8, wherein said counter means has areset signal input, and wherein said detecting means further comprisesmeans for generating at a reset signal output of said detecting meansconnected to said reset signal input a reset signal intermediate each ofsaid groups of identical synchronizing signals in order to reset saidcounter means after the printing of all the columns of an alphanumericalcharacter.

11. The printer defined in claim 8; and further comprising informationstorage means having an information signal output connected to saidinput means of said character-generating means and furthermore having anadvancement signal input for receipt of advancement signals and meansoperative for applying to said input means of said character-generatingmeans a succession of character-indicating signals each signifying analphanumerical character to be printed, and comprising means forapplying to said input means of said character-generating means the nextsignal in said succession of character-indicating signals upon receiptof an advancement signal at said advancement signal input, and meansconnecting together said advancement signal input and the last of saidcolumn-selection inputs and operative for applying to said advancementsignal input an advancement signal in response to the appearance of acolumn-selection signal at that output of said counter means connectedto said last column-selection input.

12. The printer defined in claim 8, wherein said drive means comprisesa'drive motorhaving a rotating output shaft and means interconnectingsaid output shaft and said printing head for converting the rotationalmovement of said output shaft into movement of said printing head alongsaid path, and wherein said detecting means comprises a circularinformation carrier mounted on said rotating output, shaft for rotationtherewith, said circular information carrier being provided withsuccessive groups of markings circumferentially spaced from each otherby predetermined angular intervals, and wherein the markings of eachgroup are all located on a single annular track on said informationcarrier concentric with the center of the latter, and wherein saiddetecting means further comprises a stationary reading head mounted inproximity to said an nular track for reading said markings and having anoutput constituting said synchronizing signal output for generating asynchronizing signal upon the detection of a marking.

13. The printer defined in claim 12, wherein said counter meanscomprises a binary counter having a counting signal input constitutingsaid input of said counter means and having a plurality of binaryoutputs and being operative for generating a binary-encoded signal atsaid plurality of binary outputs corresponding to the cummulative totalof the number of signals applied to said counting signal input thereof,and a binary-to-decimal decoder having a plurality of binary inputsconnected to said binary outputs of said binary counter and having aplurality of decimal outputs each connected to a respective one of saidcolumn-selection inputs.

14. The printer defined in claim 13, wherein said binary counter is aresettable binary counter having a reset signal input, and wherein saiddetecting means fuither includes resetting means for generating a resetsignal when said printing head arrives at any one of a plurality ofpredetermined locations along said path.

15. The printer defined in claim 14, wherein said circular informationcarrier is provided with a plurality of markings spaced from each otherby predetermined angular intervals and located in a further annulartrack on said information carrier concentric with the center of thelatter and a further stationary reading head positioned in proximity tosaid further track for reading the markings of said further track andhaving an output connected to said reset signal input and beingoperative for'applying to the latter a reset signal upon detection "of amarking in said further annular track.

17. The printer defined in claim 16, wherein said circular informationcarrier has the configuration of a circular disk, and wherein saidfirst-mentioned annular track and said further annular track are locatedat different radial distances from the center of said disk, and whereinsaid first-mentioned and said further reading heads are bothlight-responsive reading heads.

18. The printer defined in claim 17, wherein said markings in saidannular tracks are radially extending lines. I

19. The printer defined in claim 9, wherein said drive means comprises adrive motor having a rotating output shaft and means interconnectingsaid output shaft and said printing head for converting the rotationalmovement of said output shaft into movement of said printing head alongsaid path, and wherein said detecting means comprises a circular-diskinformation carrier mounted on said rotating output shaft for rotationtherewith, said circular information carrier being provided withsuccessive groups of markings circumferentially spaced from each otherby predetermined angular intervals and wherein the markings of each suchgroup are each located on a different annular track of said informationcarrier, and wherein said detecting means further comprises a pluralityof stationary reading heads mounted in respective proximity to saidannular tracks for reading the markings in the respective tracks, saidplurality of stationary reading heads constituting saidsignal-generating means.

20. A high-speed printer of the type operative for printingalphanumerical characters in dot-matrix form, comprising, incombination, a printing head comprised of a number of printing elementsequal to the number of dots in one column of the dot matrix; reversibledrive means driving said printing head back and forth along aband-shaped character record; synchronizing means for generatingsynchronizing signals correlated with the position of said printinghead, and including an information carrier bearing a plurality of firstmarkings and at least one second marking distinguishable from said firstmarkings, first and second detecting means operative for detecting onlysaid first markings and for detecting only said at least one secondmarking, respectively and for generating corresponding first and secondsynchronizing signals; a dot-matrix character generator; meansconnecting said character generator to said printing elements foreffecting activation of different combinations of said printing elementsin dependence upon the character registered by said character generator;read-out means connected to said first detecting means and operative foreffecting orderly readout of the dot-matrix information corresponding toa single character registered by said character generator in a pluralityof successive read-out steps respectively synchronized with successiveones of said first synchronizing signals; and a character informationsource connected to said second detecting means and operative forchanging the character registered by said character generator insynchronism with the receipt by said information source of said secondsynchronizing signal.

1. A high-sped printer for alphanumerical characters, comprising aprinting head driven back and forth along a band-shaped character recordby means of a reversible drive motor and comprised of r printingelements adapted to print as many as r dots in a column; a charactergenerator for registering characters in the form of a dot matrixcomposed of c columns and r rows and provided with r information outputsand c columnselection inputs and operative for presenting at said routputs signals representing the dots in the column corresponding towhichever one of said c inputs has a selecting signal applied thereto,said r outputs being connected to said r prinTing elements; and readingmeans for reading out said character generator column-by-column and forcausing said r printing elements to print the corresponding dot-matrixalphanumerical character column-by-column, by cyclically applyingselecting signals to successive ones of said c inputs, said readingmeans comprising a coded disk mounted on and rotating in synchronismwith the output shaft of the drive motor and provided with synchronizingmarkings arranged in first and second concentric tracks, the first trackcontaining at least one group of c equiangularly spaced markingsrespectively corresponding to said c column-selection inputs, and thesecond track containing at least one reset marking, first and seconddetectors respectively detecting the markings in the first and secondtracks and generating corresponding first and second synchronizingsignals, a binary counter having a clock input and a reset inputrespectively connected to the outputs of said first and second detectorsfor receipt of said first and second synchronizing signals,respectively, and a binary-to-decimal decoder havings its inputsconnected to the binary counter outputs and having c outputsrespectively connected to said c column-selection inputs for applyingselecting signals to the latter, and wherein said reset marking in saidsecond track is angularly offset relative to said group of markings insaid first track such that resetting of said binary counter occurssubsequent to the printing by said printing head of a completecharacter.
 2. In a high-speed printer of the type operative for printingalphanumerical characters by selecting dots of a matrix composed of dotsarranged in identical parallel columns which are spaced from each otherin the direction of a line of alphanumerical characters to be printed,in combination, a printing head including printing elements arranged inthe form of a single one of said columns; drive means for moving saidprinting head along a predetermined path extending along said direction;detecting means operative for detecting the arrival of said printinghead at successive predetermined locations along said path and operativefor generating successive synchronizing signals in response to thedetection of the arrival of said printing head at successive ones ofsaid predetermined locations, said detecting means comprising aninformation carrier bearing synchronizing markings, reading meanspositioned to read said markings and generate said synchronizingsignals, and means for effecting relative movement between saidinformation carrier and said reading means in direct correlation withthe movement of said printing head along said predetermined path, andwherein said synchronizing markings are arranged in spaced groups, thesynchronizing markings within each group being equidistantly spaced fromeach other by a first distance corresponding to the equal spacingbetween the dot-matrix columns of one dot-matrix alphanumericalcharacter to be printed, and wherein adjoining ones of said spacedgroups are spaced from each other by a different second distancecorresponding to the spacing between successive alphanumericalcharacters to be printed, and wherein the spaces intermediate successiveones of said groups are devoid of synchronizing markings like thesynchronizing markings contained in said groups; andcharacter-generating means connected to said reading means and operativeupon receipt of said successive synchronizing signals for furnishing tosaid printing elements successive groups of signals, each groupsignifying which dots of a dot-matrix column are to be printed.
 3. Theprinter defined in claim 2, wherein said information carrier is anendless information carrier.
 4. The printer defined in claim 3, whereinsaid information carrier is a circular information carrier.
 5. Theprinter defined in claim 4, wherein said means for effecting relativemovement between said information carrier and said reading meanscomPrises means connecting said circular information carrier to saiddrive means to rotate said circular information carrier in exactsynchronism with the operation of said drive means.
 6. The printerdefined in claim 5, wherein said drive means comprises a motor having arotatable output shaft and means interconnecting said rotatable outputshaft and said printing head for converting the rotational movement ofsaid output shaft into movement of said printing head along said path,and wherein said circular information carrier is mounted on saidrotatable output shaft for rotation therewith.
 7. The printer defined inclaim 2, wherein said character-generating means comprises input meansfor receiving a character-indicating signal indicative of whichalphanumerical character is to be generated, a plurality ofcolumn-selection inputs equal in number to the columns of the dot-matrixformat in which said alphanumerical characters are printed, and aplurality of outputs equal in number to the horizontal rows of thedot-matrix format in which said alphanumerical characters are printedand connected to said printing elements, connecting means connected tosaid detecting means for receipt of said synchronizing signals andconnected to said column-selection inputs and operative for applying acolumn-selection signal to successive ones of said column-selectioninputs in synchronism with the receipt of synchronizing signals fromsaid detecting means, and means operative in response to the applicationof a column-selection signal to one of said column-selection inputs forpresenting at said plurality of outputs a group of signals signifyingwhich dots of the corresponding column are to be printed by saidprinting elements.
 8. The printer defined in claim 7, wherein saiddetecting means is provided with a synchronizing signal output andcomprises means for generating successive groups of identicalsynchronizing signals at said synchronizing signal output, thesuccessive groups of identical synchronizing signals each consisting ofa number of signals equal to the number of columns in said dot-matrixformat, and wherein said connecting means comprises counter means havingan input connected to said synchronizing signal output for receivingsaid successive groups of identical synchronizing signals and having aplurality of outputs connected to different respective ones of saidcolumn-selection inputs and operative for applying a column-selectionsignal to successive ones of said column-selection inputs in synchronismwith the receipt by said counter means of the constituent signals ofeach of said groups of identical synchronizing signals.
 9. The printerdefined in claim 7, wherein said detecting means comprisessignal-generating means for generating successive groups ofdistinguishable synchronizing signals at a plurality of outputs, thesuccessive groups of distinguishable synchronizing signals eachconsisting of a number of signals equal to the number of columns in saiddot-matrix format, and wherein said connecting means comprises meansconnecting said plurality of outputs of said signal-generating means tosaid column-selection inputs and operative for applying acolumn-selection signal to different ones of said column-selectioninputs in dependence upon which one of said distinguishablesynchronizing signals is received by said connecting means.
 10. Theprinter defined in claim 8, wherein said counter means has a resetsignal input, and wherein said detecting means further comprises meansfor generating at a reset signal output of said detecting meansconnected to said reset signal input a reset signal intermediate each ofsaid groups of identical synchronizing signals in order to reset saidcounter means after the printing of all the columns of an alphanumericalcharacter.
 11. The printer defined in claim 8; and further comprisinginformation storage means having an information signal output connectedto said input means of said character-generating means And furthermorehaving an advancement signal input for receipt of advancement signalsand means operative for applying to said input means of saidcharacter-generating means a succession of character-indicating signalseach signifying an alphanumerical character to be printed, andcomprising means for applying to said input means of saidcharacter-generating means the next signal in said succession ofcharacter-indicating signals upon receipt of an advancement signal atsaid advancement signal input, and means connecting together saidadvancement signal input and the last of said column-selection inputsand operative for applying to said advancement signal input anadvancement signal in response to the appearance of a column-selectionsignal at that output of said counter means connected to said lastcolumn-selection input.
 12. The printer defined in claim 8, wherein saiddrive means comprises a drive motor having a rotating output shaft andmeans interconnecting said output shaft and said printing head forconverting the rotational movement of said output shaft into movement ofsaid printing head along said path, and wherein said detecting meanscomprises a circular information carrier mounted on said rotating outputshaft for rotation therewith, said circular information carrier beingprovided with successive groups of markings circumferentially spacedfrom each other by predetermined angular intervals, and wherein themarkings of each group are all located on a single annular track on saidinformation carrier concentric with the center of the latter, andwherein said detecting means further comprises a stationary reading headmounted in proximity to said annular track for reading said markings andhaving an output constituting said synchronizing signal output forgenerating a synchronizing signal upon the detection of a marking. 13.The printer defined in claim 12, wherein said counter means comprises abinary counter having a counting signal input constituting said input ofsaid counter means and having a plurality of binary outputs and beingoperative for generating a binary-encoded signal at said plurality ofbinary outputs corresponding to the cummulative total of the number ofsignals applied to said counting signal input thereof, and abinary-to-decimal decoder having a plurality of binary inputs connectedto said binary outputs of said binary counter and having a plurality ofdecimal outputs each connected to a respective one of saidcolumn-selection inputs.
 14. The printer defined in claim 13, whereinsaid binary counter is a resettable binary counter having a reset signalinput, and wherein said detecting means further includes resetting meansfor generating a reset signal when said printing head arrives at any oneof a plurality of predetermined locations along said path.
 15. Theprinter defined in claim 14, wherein said circular information carrieris provided with a plurality of markings spaced from each other bypredetermined angular intervals and located in a further annular trackon said information carrier concentric with the center of the latter anda further stationary reading head positioned in proximity to saidfurther track for reading the markings of said further track and havingan output connected to said reset signal input and being operative forapplying to the latter a reset signal upon detection of a marking insaid further annular track.
 16. The printer defined in claim 15, whereinthe markings in the first-mentioned annular track are arranged incircumferentially successive groups each composed of a plurality ofmarkings equal in number to the number of columns in said dot-matrixformat, and wherein the markings in said further annular track arearranged intermediate said groups of markings in said first-mentionedannular track, and wherein the first-mentioned reading head and saidfurther reading head are located on a diametral line of said circularinformation carrier.
 17. The printer defined in claim 16, wherein saIdcircular information carrier has the configuration of a circular disk,and wherein said first-mentioned annular track and said further annulartrack are located at different radial distances from the center of saiddisk, and wherein said first-mentioned and said further reading headsare both light-responsive reading heads.
 18. The printer defined inclaim 17, wherein said markings in said annular tracks are radiallyextending lines.
 19. The printer defined in claim 9, wherein said drivemeans comprises a drive motor having a rotating output shaft and meansinterconnecting said output shaft and said printing head for convertingthe rotational movement of said output shaft into movement of saidprinting head along said path, and wherein said detecting meanscomprises a circular-disk information carrier mounted on said rotatingoutput shaft for rotation therewith, said circular information carrierbeing provided with successive groups of markings circumferentiallyspaced from each other by predetermined angular intervals and whereinthe markings of each such group are each located on a different annulartrack of said information carrier, and wherein said detecting meansfurther comprises a plurality of stationary reading heads mounted inrespective proximity to said annular tracks for reading the markings inthe respective tracks, said plurality of stationary reading headsconstituting said signal-generating means.
 20. A high-speed printer ofthe type operative for printing alphanumerical characters in dot-matrixform, comprising, in combination, a printing head comprised of a numberof printing elements equal to the number of dots in one column of thedot matrix; reversible drive means driving said printing head back andforth along a band-shaped character record; synchronizing means forgenerating synchronizing signals correlated with the position of saidprinting head, and including an information carrier bearing a pluralityof first markings and at least one second marking distinguishable fromsaid first markings, first and second detecting means operative fordetecting only said first markings and for detecting only said at leastone second marking, respectively and for generating corresponding firstand second synchronizing signals; a dot-matrix character generator;means connecting said character generator to said printing elements foreffecting activation of different combinations of said printing elementsin dependence upon the character registered by said character generator;read-out means connected to said first detecting means and operative foreffecting orderly read-out of the dot-matrix information correspondingto a single character registered by said character generator in aplurality of successive read-out steps respectively synchronized withsuccessive ones of said first synchronizing signals; and a characterinformation source connected to said second detecting means andoperative for changing the character registered by said charactergenerator in synchronism with the receipt by said information source ofsaid second synchronizing signal.